Calendula is commonly known as marigold. It is an annual flower belonging to the Aster or Compositae family. The flower is native to Asia and southern Europe.

Calendula has been used as medicine since the 12th century in central Europe and the Mediterranean. It has been applied to the skin as a possible treatment for minor wounds, infections, burns, bee stings, sunburn, and warts.

Early evidence suggests that applying calendula ointment to the skin may prevent allergic reactions caused by radiation therapy for breast cancer.

Further research is needed before firm conclusions can be made on any medical use of calendula.

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

GRADE *

Calendula extract has been studied for the treatment of anal fissures. However, further details are lacking and more study is needed.

C

A gel containing calendula and other plant extracts may help prevent skin cancer formation, according to an early study. However, more research is needed to confirm these findings.

C

Early study suggests that a calendula ointment may be more effective at reducing diaper rash, compared to an aloe cream. Further study is needed.

C

There is a lack of evidence in support of calendula for the treatment of ear infection. Combination products containing calendula have been studied for this condition. However, more research is needed in this area.

C

Early evidence suggests that calendula applied to the skin may help prevent allergic reactions, pain, and redness during radiation therapy. However, more high-quality research is needed in this area before firm conclusions can be made.

C

Calendula has been studied in the treatment of lichen planus, a type of rash that can occur on the skin or inside the mouth. Although early results are promising, more research is needed in this area.

C

Calendula has been studied as a possible therapy after skin surgery. A cream containing calendula was found to have benefits when applied to the skin. Calendula is believed to have anti-inflammatory activity. However, human evidence is lacking and further study is needed.

C

A calendula-containing product has been found to improve vaginal dryness in women with menopause when applied to the skin. More research is needed to confirm these findings and to determine the effects of calendula alone.

C

Calendula has been studied for the treatment of venous leg ulcers. Early results suggest that marigold extract may promote the healing of lower leg venous ulcers. However, further study is needed in this area.

C

Calendula has been suggested as a treatment for minor skin wounds and early studies suggest that calendula may promote wound healing. However, more research is needed before firm conclusions can be made.

C

* Key to grades

A: Strong scientific evidence for this useB: Good scientific evidence for this useC: Unclear scientific evidence for this useD: Fair scientific evidence for this use (it may not work)F: Strong scientific evidence against this use (it likley does not work)

Tradition / Theory
The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.

Ointments or tincture compresses have been applied to affected areas as needed. The expert panels German Commission E and the European Scientific Cooperative on Phytotherapy report that a 2-5 percent ointment is often used. Calendula products may be applied 3-4 times daily as needed. A 1:1 tincture in 40 percent alcohol or 1:5 in 90 percent alcohol may be diluted at least 1:3 with freshly boiled water for compresses.

To protect skin during radiation therapy, an ointment containing calendula in a petroleum jelly base has been applied to the skin at least twice daily, for the duration of radiation treatment. Calendula ointment has been applied at the start of radiation therapy, continuing until the end of treatment.

For skin care, calendula facial creams have been applied to the face once daily for eight weeks before bed.

To treat venous leg ulcers, an ointment containing marigold extract in a neutral base has been applied to the skin twice daily for three weeks.

Children (under 18 years old)

To treat diaper rash, a calendula ointment has been applied to the skin three times daily for ten days, or stopped when healing occurred sooner than ten days.

Safety
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Allergies

Avoid if allergic or sensitive to calendula (marigold), its parts, or members of the Aster or Compositae family, such as ragweed, chrysanthemums, or daisies.

Severe allergic reaction and skin symptoms have been reported with exposure to calendula. There may be cross-sensitivity with arnica, nickel, Myroxylon pereirae resin, propolis, and colophonium.

Side Effects and Warnings

Calendula is likely safe when used as a spice, natural seasoning, or flavoring, and when used in cosmetics.

Drowsiness or sedation may occur. Use caution if taking sedatives or driving or operating heavy machinery.

Calendula may cause low blood pressure. Caution is advised in people taking drugs or herbs and supplements that lower blood pressure.

Calendula may lower blood sugar levels. Caution is advised in people with diabetes or low blood sugar, and in those taking drugs, herbs, or supplements that affect blood sugar. Blood sugar levels may need to be monitored by a qualified healthcare professional, including a pharmacist, and medication adjustments may be necessary.

Use cautiously in people taking agents that may affect the immune system. Calendula may enhance immune response.

Use cautiously in people who have kidney disorders. High doses of calendula (up to 5 grams per kilogram) may cause kidney problems.

Use cautiously in children, due to a lack of safety data.

Avoid in pregnant or breastfeeding women. Calendula may cause abortion.

Avoid if allergic or sensitive to calendula (marigold), its parts, or members of the Aster or Compositae family, such as ragweed, chrysanthemums, or daisies.

Avoid long-term use, due to the risk of side effects.

Avoid taking by mouth at levels above those commonly found in the diet.

Calendula may increase kidney and liver problems caused by some other drugs. High doses of calendula (up to 5 grams per kilogram) may lead to liver toxicity.

Calendula may lower blood sugar levels. Caution is advised when using medications that may also lower blood sugar. People taking drugs for diabetes by mouth or insulin should be monitored closely by a qualified healthcare professional, including a pharmacist. Medication adjustments may be necessary.

Calendula may increase the amount of drowsiness caused by some drugs. Examples include benzodiazepines such as lorazepam (Ativan®) or diazepam (Valium®), barbiturates such as phenobarbital, narcotics such as codeine, some antidepressants, and alcohol. Caution is advised while driving or operating machinery.

The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.